Differential associations between abnormal cardiac left ventricular geometry types and cerebral white matter disease

OBJECTIVES

Reduced cardiac outflow due to left ventricular hypertrophy has been suggested as a potential risk factor for development of cerebral white matter disease. Our study aimed to examine the correlation between left ventricular geometry and white matter disease volume to establish a clearer understanding of their relationship, as it is currently not well-established.

METHODS

Consecutive patients from 2016 to 2021 who were ≥18 years and underwent echocardiography, cardiac MRI, and brain MRI within one year were included. Four categories of left ventricular geometry were defined based on left ventricular mass index and relative wall thickness on echocardiography. White matter disease volume was quantified using an automated algorithm applied to axial T2 FLAIR images and compared across left ventricular geometry categories.

RESULTS

We identified 112 patients of which 34.8 % had normal left ventricular geometry, 20.5 % had eccentric hypertrophy, 21.4 % had concentric remodeling, and 23.2 % had concentric hypertrophy. White matter disease volume was highest in patients with concentric hypertrophy and concentric remodeling, compared to eccentric hypertrophy and normal morphology with a trend-P value of 0.028. Patients with higher relative wall thickness had higher white matter disease volume (10.73 ± 10.29 cc vs 5.89 ± 6.46 cc, P = 0.003), compared to those with normal relative wall thickness.

CONCLUSION

Our results showed that abnormal left ventricular geometry is associated with higher white matter disease burden, particularly among those with abnormal relative wall thickness. Future studies are needed to explore causative relationships and potential therapeutic options that may mediate the adverse left ventricular remodeling and its effect in slowing white matter disease progression.

Asymptomatic Females Are at Higher Risk for Perioperative TIA/Stroke and Males Are at Higher Risk for Long-Term Mortality after Carotid Artery Stenting: A Vascular Quality Initiative Analysis

The study aims to review the sex differences with respect to transient ischemic attack (TIA)/stroke and death in the perioperative period and on long-term follow-up among asymptomatic patients treated with carotid stenting (CAS) in the vascular quality initiative (VQI). All cases reported to VQI of asymptomatic CAS (ACAS) patients were reviewed. The primary end point was risk of TIA/stroke and death in the in-hospital perioperative period and in the long-term follow-up. The secondary end point was to evaluate predictors of in-hospital perioperative TIA/stroke and mortality on long-term follow-up after CAS. There were 22,079 CAS procedures captured from January 2005 to April 2019. There were 5,785 (62.7%) patients in the ACAS group. The rate of in-hospital TIA/stroke was higher in female patients (2.7 vs. 1.87%, p  = 0.005) and the rate of death was not significant (0.03 vs. 0.07%, p  = 0.66). On multivariable logistic regression analysis, prior/current smoking history (odds ratio = 0.58 [95% confidence interval or CI = 0.39-0.87]; p  = 0.008) is a predictor of in-hospital TIA/stroke in females. The long-term all-cause mortality is significantly higher in male patients (26.9 vs. 15.7%, p  < 0.001). On multivariable Cox-regression analysis, prior/current smoking history (hazard ratio or HR = 1.17 [95% CI = 1.01-1.34]; p  = 0.03), coronary artery disease or CAD (HR = 1.15 [95% CI = 1.03-1.28]; p  = 0.009), chronic obstructive pulmonary disease or COPD (HR = 1.73 [95% CI = 1.55-1.93]; p  < 0.001), threat to life American Society of Anesthesiologists (ASA) class (HR = 2.3 [95% CI = 1.43-3.70]; p  = 0.0006), moribund ASA class (HR = 5.66 [95% CI = 2.24-14.29]; p  = 0.0003), and low hemoglobin levels (HR = 0.84 [95% CI = 0.82-0.86]; p  < 0.001) are the predictors of long-term mortality. In asymptomatic carotid disease patients, women had higher rates of in-hospital perioperative TIA/stroke and a predictor of TIA/stroke is a prior/current history of smoking. Meanwhile, long-term all-cause mortality is higher for male patients compared with their female counterparts. Predictors of long-term mortality are prior/current smoking history, CAD, COPD, higher ASA classification of physical status, and low hemoglobin level. These data should be considered prior to offering CAS to asymptomatic female and male patients and careful risks versus benefits discussion should be offered to each individual patient.

Greater burden of white matter lesions and silent infarcts ipsilateral to carotid stenosis

OBJECTIVES

Carotid stenosis may cause silent cerebrovascular disease (CVD) through atheroembolism and hypoperfusion. If so, revascularization may slow progression of silent CVD. We aimed to compare the presence and severity of silent CVD to the degree of carotid bifurcation stenosis by cerebral hemisphere.

MATERIALS AND METHODS

Patients age ≥40 years with carotid stenosis >50% by carotid ultrasound who underwent MRI brain from 2011-2015 at Mayo Clinic were included. Severity of carotid stenosis was classified by carotid duplex ultrasound as 50-69% (moderate), 70-99% (severe), or occluded. White matter lesion (WML) volume was quantified using an automated deep-learning algorithm applied to axial T2 FLAIR images. Differences in WML volume and prevalent silent infarcts were compared across hemispheres and severity of carotid stenosis.

RESULTS

Of the 183 patients, mean age was 71±10 years, and 39.3% were female. Moderate stenosis was present in 35.5%, severe stenosis in 46.5% and occlusion in 18.0%. Patients with carotid stenosis had greater WML volume ipsilateral to the side of carotid stenosis than the contralateral side (mean difference, 0.42±0.21cc, p=0.046). Higher degrees of stenosis were associated with greater hemispheric difference in WML volume (moderate vs. severe; 0.16±0.27cc vs 0.74±0.31cc, p=0.009). Prevalence of silent infarct was 23.5% and was greater on the side of carotid stenosis than the contralateral side (hemispheric difference 8.8%±3.2%, p=0.006). Higher degrees of stenosis were associated with higher burden of silent infarcts (moderate vs severe, 10.8% vs 31.8%; p=0.002).

CONCLUSIONS

WML and silent infarcts were greater on the side of severe carotid stenosis.

When Will We Have What We Need to Advise Patients How to Manage Their Carotid Stenosis?: Lessons From SPACE-2

The recently published SPACE-2 trial (Stent-Supported Percutaneous Angioplasty of the Carotid Artery Versus Endarterectomy-2) compared 3 treatments to prevent stroke in patients with asymptomatic carotid stenosis ≥70%: (1) carotid endarterectomy plus best medical treatment (BMT), (2) transfemoral carotid artery stenting plus BMT, or (3) BMT alone. Because of low enrollment, the findings of similar safety and efficacy for carotid endarterectomy, carotid artery stenting, or BMT alone were inconclusive. Publication of the CREST (Carotid Revascularization and Medical Management for Asymptomatic Carotid Stenosis Trial)-2 results should provide level A evidence that has been lacking for 2 to 3 decades, to guide treatment of asymptomatic patients with severe carotid stenosis. For symptomatic patients with ≥70% stenosis, no trials are underway to update the degree of benefit reported for carotid endarterectomy by NASCET (North American Carotid Endarterectomy Trial) and ECST (European Carotid Surgery Trial), published in 1991. Subsequently, the use of cigarettes has plummeted, and major improvements in medical treatments and in carotid revascularization have emerged. These advances have coincided with abrupt decline in the clinical end points necessary for treatment comparisons in procedural trials. One of the advances in the invasive management of carotid disease has been transcarotid artery revascularization, already with limited approval by the US Food and Drug Administration. Establishing safety and efficacy of transcarotid artery revascularization compared with carotid endarterectomy, carotid artery stenting, or BMT alone may be challenging because of enrollment, regulatory, and funding barriers to design and complete an adequately powered randomized trial.

No Sex Differences in the Prevalence of Intracranial Aneurysms in Patients with Ascending Thoracic Aortic Aneurysms: A Multi-Center Experience

BACKGROUND

Previous studies suggest a coprevalence of intracranial aneurysms (IA) in patients with infrarenal abdominal aortic aneurysms (AAA). We reviewed our multicenter experience in the detection/treatment of IAs in patients with ascending thoracic aortic aneurysms (ATAA) relative to patients without ATAA.

METHODS

Surgical cases of ATAA repaired at 3 sites from January 1998 to December 2018 were retrospectively reviewed. Out of these patients, those with intracranial vascular imaging were selected for our study, and these individuals were concurrently randomly matched with a control group of patients who underwent intracranial vascular imaging without an ATAA in a 1:1 ratio by age, sex, smoking history, and year of intracranial vascular imaging. Conditional logistic regression was used to calculate odds ratios (OR).

RESULTS

We reviewed 2176 ATAA repairs. 74% (n = 1,615) were men. Intracranial vascular imaging was available in 298 (13.7%) patients. Ninteen patients were found to have 22 IAs for a prevalence of 6.4%. Mean size of IA was 4.6 ± 3.3 mm; mean age at IA detection, 63.4 ± 12.1 years. IA was present on head imaging in 4.7% of male and 12.5% of female patients. Eleven (58%) patients were men. The OR of having IA in female versus male patients is 2.90, 95% confidence interval [CI] [1.08-7.50], P = 0.029. Time from IA diagnosis to ATAA repair was 1.7 ± 116.2 months. Two patients underwent treatment for IA, one ruptured and one unruptured. All were diagnosed before ATAA repair. Treatment included 1 clipping and 1 coiling with subsequent reintervention of the coiling using a flow diversion device. In the matched group of patients who had intracranial vascular imaging without ATAA, the rate of IA is 5.0%. IA was detected in 3.8% of males and 9.4% of female patients for an OR of 2.59, 95% CI [0.84-7.47], P = 0.083. Association within our study and matched groups, the OR of developing an IA with and without ATAA was not statistically significant 1.29, 95% CI [0.642.59], P = 0.48. There was also no evidence of sex differences in the association of ATAA with IA (interaction P = 0.88). The OR for the association of ATAA with IA was 1.33, 95% CI [0.46-3.84], P = 0.59 in females and 1.25, 95% CI [0.49-3.17], P = 0.64 in males.

CONCLUSIONS

Our study found that IA was present in 6.4% of patients with ATAA who had intracranial vascular imaging available. The odds of IA were 1.29 times higher than a matched cohort of patients who had intracranial vascular imaging without ATAA but this failed to achieve statistical significance. We found that the odds of IA were more than 2 times higher in females than males for both those with ATAA (OR = 2.90) and those without ATAA (OR = 2.59); however, it only reached statistical significance in those with ATAA.

Adapting to Evolving Technologies and Treatment Guidelines in a Procedural Trial: A Qualitative Review of the CREST-2 Experience

Multiple challenges confront procedural trials, including slow enrollment, lack of equipoise among patients and physicians, and failure to achieve adequate masking. Nonetheless, randomized clinical trials provide the best evidence of efficacy. The evolution of technology, techniques, and standards of care during the conduct of procedural trials challenges external validity. Herein, we review how a multicenter trial of revascularization of asymptomatic carotid arteries for stroke prevention has managed changes in treating carotid stenosis and medical management of atherothrombotic disease.

Cortical Thinning in High-Grade Asymptomatic Carotid Stenosis

BACKGROUND AND PURPOSE

High-grade carotid artery stenosis may alter hemodynamics in the ipsilateral hemisphere, but consequences of this effect are poorly understood. Cortical thinning is associated with cognitive impairment in dementia, head trauma, demyelination, and stroke. We hypothesized that hemodynamic impairment, as represented by a relative time-to-peak (TTP) delay on MRI in the hemisphere ipsilateral to the stenosis, would be associated with relative cortical thinning in that hemisphere.

METHODS

We used baseline MRI data from the NINDS-funded Carotid Revascularization and Medical Management for Asymptomatic Carotid Stenosis-Hemodynamics (CREST-H) study. Dynamic contrast susceptibility MR perfusion-weighted images were post-processed with quantitative perfusion maps using deconvolution of tissue and arterial signals. The protocol derived a hemispheric TTP delay, calculated by subtraction of voxel values in the hemisphere ipsilateral minus those contralateral to the stenosis.

RESULTS

Among 110 consecutive patients enrolled in CREST-H to date, 45 (41%) had TTP delay of at least 0.5 seconds and 9 (8.3%) subjects had TTP delay of at least 2.0 seconds, the maximum delay measured. For every 0.25-second increase in TTP delay above 0.5 seconds, there was a 0.006-mm (6 micron) increase in cortical thickness asymmetry. Across the range of hemodynamic impairment, TTP delay independently predicted relative cortical thinning on the side of stenosis, adjusting for age, sex, hypertension, hemisphere, smoking history, low-density lipoprotein cholesterol, and preexisting infarction (P=0.032).

CONCLUSIONS

Our findings suggest that hemodynamic impairment from high-grade asymptomatic carotid stenosis may structurally alter the cortex supplied by the stenotic carotid artery.

Stroke Symptoms As a Surrogate in Stroke Primary Prevention Trials: The CREST Experience

BACKGROUND

and Purpose: The use of surrogate endpoints can decrease sample size while maintaining statistical power. This report considers incident stroke symptoms as a surrogate endpoint in a post-hoc analysis of asymptomatic patients from the multicenter, randomized Carotid Revascularization Endarterectomy vs. Stenting Trial (CREST).

METHODS

CREST assessed stroke symptoms using the Questionnaire for Verifying Stroke-free Status (QVSS) at baseline and follow-up. While the primary analysis of CREST defined "asymptomatic" as having been free of stroke/TIA for 180 days, herein the population was further restricted by requiring no stroke symptoms at baseline. Incident adjudicated stroke was defined the same as for the primary analysis; incident stroke symptoms was defined as developing ≥1 stroke symptom in follow-up. Treatment differences between stenting (CAS) and endarterectomy (CEA) were assessed for three endpoints: adjudicated stroke, stroke symptoms, and adjudicated stroke or stroke symptoms.

RESULTS

The cohort included 826 of the 1181 asymptomatic patients in CREST. Adjudicated stroke events occurred in 44 patients and incident stroke symptoms occurred in 183. Analysis of adjudicated stroke endpoints demonstrated a non-significant hazard ratio (HR) for CAS compared to CEA of 1.02 (95% confidence interval [CI], 0.57-1.85). The corresponding HR for the incident stroke symptoms outcome was 1.54 (95% CI, 1.15-2.08), and the HR for the composite outcome of adjudicated stroke or incident symptoms was 1.38 (95% CI, 1.04-1.83), both significant.

CONCLUSIONS

The low stroke event rates in asymptomatic patients challenges the assessment of CAS-versus-CEA treatment differences. Incorporating incident stroke symptoms as a surrogate outcome increased the number of events by over 4-fold. The analysis demonstrated a previously unreported significant difference in cerebrovascular risk with CAS compared to CEA. We propose that broadening the endpoints of primary stroke prevention trials to include surrogate events like incident stroke symptoms could make trials more feasible.

Lessons From ACST-2

The recent 130-center, international, second ACST trial (Asymptomatic Carotid Surgery Trial) involving 3625 patients found that regardless of whether a patient underwent stenting or endarterectomy, the periprocedural risk of disabling or fatal stroke was about 1% and the 5-year estimated risk of nonprocedural disabling or fatal stroke was 2.5%. With advances in technique, technology, and patient selection, stenting done by appropriately trained and experienced operators can achieve safety and efficacy comparable to endarterectomy for asymptomatic patients. The ongoing CREST-2 trial (Carotid Revascularization and Medical Management for Asymptomatic Carotid Stenosis Trial) will clarify whether revascularization, by either stenting or endarterectomy, remains an important therapeutic goal in the setting of modern intensive medical therapy.

Safety of the transradial approach to carotid stenting

BACKGROUND

The multicenter prospective CREST-2 Registry (C2R) provides recent experience in performing carotid artery stenting (CAS) for interventionists to ensure safe performance of CAS.

OBJECTIVE

To determine the periprocedural safety of CAS performed using a transradial approach relative to CAS performed using a transfemoral approach.

METHODS

Patients with ≥70% asymptomatic and ≥50% symptomatic carotid stenosis, ≤80 years of age and at standard or high risk for carotid endarterectomy (CEA) are eligible for the C2R. The primary endpoint was a composite of severe access-related complications. Comparisons were made using propensity-score matched logistic regression.

RESULTS

The mean age of the cohort was 67.6 ± 8.2 years and 1906 (35.1%) were female. Indications for CAS included 4063 (74.9%) for primary atherosclerosis. A total of 2868 (52.8%) cases underwent CAS for asymptomatic disease. Transradial access was used in 213 (3.9%) patients. The transradial cohort had lower use of general anesthesia (1.5% vs. 6.3%, p = 0.007) and higher use of distal embolic protection (96.7% vs. 89.4%, p = 0.0004). There were no significant differences between radial and femoral access groups in terms of a composite of major access-related complications (0% vs. 1.1%) or a composite of periprocedural stroke or death (3.3% vs. 2.4%; OR = 1.4 [confidence intervals 0.6, 3.1]; p = 0.42).

CONCLUSION

We found no significant differences in rates of major access-related complications or periprocedural stroke or death with CAS performed using transradial compared to transfemoral access. Our results support incorporation of the transradial approach to clinical trials comparing CAS to other revascularization techniques.

Health Screening Program to Enhance Enrollment of Women and Minorities in CREST-2

BACKGROUND AND PURPOSE

The CREST-2 (Carotid Revascularization and Medical Management for Asymptomatic Carotid Stenosis Trial) consists of 2 parallel randomized stroke prevention trials in patients with asymptomatic high-grade stenosis of the cervical carotid artery. The purpose of this report is to detail the outcomes of a health screening effort to increase trial enrollment of women and minorities.

METHODS

Life Line screening (LLS) conducts nationwide screening for vascular disease. Screenings within a 50-mile radius of each CREST-2 center were identified for participation in a joint CREST-LLS program over the course of one year (November 2018 to October 2019) whereby patients with an abnormal carotid ultrasound were referred to the local CREST-2 center for further workup, management, and potential consideration for trial enrollment.

RESULTS

LLS completed the screening of 588 198 individuals in 29 732 zip codes across the United States. Of those, 230 021 individuals were screened at events occurring near a CREST-2 clinical center and 646 (0.3%) were found to have abnormal carotid ultrasound findings. Each of the 646 individuals was contacted by CREST-LLS program staff for permission to be referred to their local CREST-2 center; 200 (31%) consented to be contacted by CREST-2. Of those, 39 (19.5%) agreed to be, and were, evaluated at their local CREST-2 center. High-grade stenosis was confirmed in 27 patients. A total of 3 patients were eligible for the trial and were enrolled, one woman but no racial/ethnic minorities.

CONCLUSIONS

The LLS program appears to identify community-living individuals with high-grade carotid stenosis through ultrasonography. However, the prevalence of abnormal carotid findings was low. In addition, screening and offering participation into the CREST-2 trial had no substantial impact on the proportion of women and minorities enrolled in the trial. Additional innovative strategies are needed to promote enrollment of diverse patients with carotid stenosis into stroke prevention trials.

Treatment of carotid stenosis in asymptomatic, non-octogenarian, standard risk patients with stenting versus endarterectomy trials

OBJECTIVE

Asymptomatic carotid stenosis is the most frequent indication for carotid endarterectomy (CEA) in the United States. Published trials and guidelines support CEA indications in selected patients with longer projected survival and when periprocedural complications are low. Transfemoral carotid artery stenting with embolic protection (CAS) is a newer treatment option. The objective of this study was to compare outcomes in asymptomatic, nonoctogenarian patients treated with CAS vs CEA.

METHODS

Patient-level data was analyzed from 2544 subjects with ≥70% asymptomatic carotid stenosis who were randomized to CAS or CEA in addition to standard medical therapy. One trial enrolled 1091 (548 CAS, 543 CEA) and another enrolled 1453 (1089 CAS, 364 CEA) asymptomatic patients less than 80 years old (upper age eligibility). Independent neurologic assessment and routine cardiac enzyme screening were performed. The prespecified, primary composite endpoint was any stroke, myocardial infarction, or death during the periprocedural period or ipsilateral stroke within 4 years after randomization.

RESULTS

There was no significant difference in the primary endpoint between CAS and CEA (5.3% vs 5.1%; hazard ratio, 1.02; 95% confidence interval, 0.7-1.5; P = .91). Periprocedural rates for the components are (CAS vs CEA): any stroke (2.7% vs 1.5%; P = .07), myocardial infarction (0.6% vs 1.7%; P = .01), death (0.1% vs 0.2%; P = .62), and any stroke or death (2.7% vs 1.6%; P = .07). After this period, the rates of ipsilateral stroke were similar (2.3% vs 2.2%; P = .97).

CONCLUSIONS

In a pooled analysis of two large randomized trials of CAS and CEA in asymptomatic, nonoctogenarian patients, CAS achieves comparable short- and long-term results to CEA.

Baseline Cognitive Impairment in Patients With Asymptomatic Carotid Stenosis in the CREST-2 Trial

BACKGROUND AND PURPOSE

Studies of carotid artery disease have suggested that high-grade stenosis can affect cognition, even without stroke. The presence and degree of cognitive impairment in such patients have not been reported and compared with a demographically matched population-based cohort.

METHODS

We studied cognition in 1000 consecutive CREST-2 (Carotid Revascularization and Medical Management for Asymptomatic Carotid Stenosis Trial) patients, a treatment trial for asymptomatic carotid disease. Cognitive assessment was after randomization but before assigned treatment. The cognitive battery was developed in the general population REGARDS Study (Reasons for Geographic and Racial Differences in Stroke), involving Word List Learning Sum, Word List Recall, and Word List fluency for animal names and the letter F. The carotid stenosis patients were >45 years old with ≥70% asymptomatic carotid stenosis and no history of prevalent stroke. The distribution of cognitive performance for the patients was standardized, accounting for age, race, and education using performance from REGARDS, and after further adjustment for hypertension, diabetes, dyslipidemia, and smoking. Using the Wald Test, we tabulated the proportion of Z scores less than the anticipated deviate for the population-based cohort for representative percentiles.

RESULTS

There were 786 baseline assessments. Mean age was 70 years, 58% men, and 52% right-sided stenosis. The overall Z score for patients was significantly below expected for higher percentiles (P<0.0001 for 50th, 75th, and 95th percentiles) and marginally below expected for the 25th percentile (P=0.015). Lower performance was attributed largely to Word List Recall (P<0.0001 for all percentiles) and for Word List Learning (50th, 75th, and 95th percentiles below expected, P≤0.01). The scores for left versus right carotid disease were similar.

CONCLUSIONS

Baseline cognition of patients with severe carotid stenosis showed below normal cognition compared to the population-based cohort, controlling for demographic and cardiovascular risk factors. This cohort represents the largest group to date to demonstrate that poorer cognition, especially memory, in this disease.

REGISTRATION

URL: https://www.clinicaltrials.gov; Unique identifier: NCT02089217.

Plasma neurofilament light predicts mortality in patients with stroke

Given the heterogeneity of stroke brain injury, there is a clear need for a biomarker that determines the degree of neuroaxonal injury across stroke types. We evaluated whether blood neurofilament light (NFL) would fulfill this purpose for patients with acute cerebral infarction (ACI; N = 227), aneurysmal subarachnoid hemorrhage (aSAH; N = 58), or nontraumatic intracerebral hemorrhage (ICH; N = 29). We additionally validated our findings in two independent cohorts of patients with ICH (N = 96 and N = 54) given the scarcity of blood biomarker studies for this deadliest stroke type. Compared to healthy individuals (N = 79 and N = 48 for the discovery and validation cohorts, respectively), NFL was higher for all stroke types. NFL associated with radiographic markers of brain tissue damage. It correlated with the extent of early ischemic injury in patients with ACI, hemorrhage severity in patients with aSAH, and intracranial hemorrhage volume in patients with ICH. In all patients, NFL independently correlated with scores from the NIH Stroke Scale, the modified Rankin Scale, and the Mini-Mental State Examination at blood draw, which respectively assess neurological, functional, and cognitive status. Furthermore, higher NFL concentrations independently associated with 3- or 6-month functional disability and higher all-cause mortality. These data support NFL as a uniform method to estimate neuroaxonal injury and forecast mortality regardless of stroke mechanism. As a prognostic biomarker, blood NFL has the potential to assist with planning supportive and rehabilitation services and improving clinical trial efficiency for stroke therapeutics and devices.

Race Differences in High-Grade Carotid Artery Stenosis

Background and Purpose

Despite a higher incidence of stroke and a more adverse cardiovascular risk factor profile in Blacks and Hispanics compared with Whites, carotid artery revascularization is performed less frequently among these subpopulations. We assessed racial differences in high-grade (≥70% diameter-reducing) carotid stenosis.

Methods

Consecutive clients in a Nationwide Life Line for-Profit Service to screen for vascular disease, 2005 to 2019 were evaluated in a cross-sectional study. The prevalence of high-grade stenosis, defined by a carotid ultrasound peak systolic velocity of ≥230 cm/s, was assessed. Participants self-identified as White, Black, Hispanic, Asian, Native American, or other. Race/ethnic differences were assessed using Poisson regression. The number of individuals in the United States with high-grade stenosis was estimated by applying prevalence estimates to 2015 US Census population estimates.

Results

The prevalence of high-grade carotid stenosis was estimated in 6 130 481 individuals. The prevalence of high-grade stenosis was higher with increasing age in all race-sex strata. Generally, Blacks and Hispanics had a lower prevalence of high-grade stenosis compared with Whites, while Native Americans had a higher prevalence. For example, for men aged 55 to 65, the relative risk of stenosis compared with Whites was 0.40 (95% CI, 0.29–0.55) and 0.61 (95% CI, 0.46–0.81) for Blacks and Hispanics, respectively; and 1.53 (95% CI, 1.12–2.10) for Native Americans. When these prevalence estimates were applied to the Census estimates of the US population, an estimated 327 721 individuals have high-grade stenosis, of whom 7% are Black, 7% Hispanic, and 43% women.

Conclusions

Despite their having a more adverse cardiovascular risk profile, there was a lower prevalence of high-grade carotid artery stenosis for both the Black and Hispanic relative to the White clients. This lower prevalence of high-grade stenosis is a potential contributor to the lower use of carotid revascularization procedures in these minority populations.

Editor's Choice - Risk of Stroke before Revascularisation in Patients with Symptomatic Carotid Stenosis: A Pooled Analysis of Randomised Controlled Trials

OBJECTIVE

Current guidelines recommending rapid revascularisation of symptomatic carotid stenosis are largely based on data from clinical trials performed at a time when best medical therapy was potentially less effective than today. The risk of stroke and its predictors among patients with symptomatic carotid stenosis awaiting revascularisation in recent randomised controlled trials (RCTs) and in medical arms of earlier RCTs was assessed.

METHODS

The pooled data of individual patients with symptomatic carotid stenosis randomised to stenting (CAS) or endarterectomy (CEA) in four recent RCTs, and of patients randomised to medical therapy in three earlier RCTs comparing CEA vs. medical therapy, were compared. The primary outcome event was any stroke occurring between randomisation and treatment by CAS or CEA, or within 120 days after randomisation.

RESULTS

A total of 4 754 patients from recent trials and 1 227 from earlier trials were included. In recent trials, patients were randomised a median of 18 (IQR 7, 50) days after the qualifying event (QE). Twenty-three suffered a stroke while waiting for revascularisation (cumulative 120 day risk 1.97%, 95% confidence interval [CI] 0.75 - 3.17). Shorter time from QE until randomisation increased stroke risk after randomisation (χ² = 6.58, p = .011). Sixty-one patients had a stroke within 120 days of randomisation in the medical arms of earlier trials (cumulative risk 5%, 95% CI 3.8 - 6.2). Stroke risk was lower in recent than earlier trials when adjusted for time between QE and randomisation, age, severity of QE, and degree of carotid stenosis (HR 0.47, 95% CI 0.25 - 0.88, p = .019).

CONCLUSION

Patients with symptomatic carotid stenosis enrolled in recent large RCTs had a lower risk of stroke after randomisation than historical controls. The added benefit of carotid revascularisation to modern medical care needs to be revisited in future studies. Until then, adhering to current recommendations for early revascularisation of patients with symptomatic carotid stenosis considered to require invasive treatment is advisable.

Abstract 8: Retinopathy is Associated With Stroke, Dementia, and Mortality

Introduction: Retinal microvascular abnormalities have been associated with stroke, but their association with dementia and death is less well described. We tested the hypothesis that retinopathy is associated with stroke, dementia, and age-adjusted mortality.

Methods: Data were obtained from the US National Health and Nutrition Examination Surveys from 2005 to 2008, with linked mortality through 2015. Severity of retinopathy was defined as no retinopathy, mild nonproliferative retinopathy (NPR), moderate-severe NPR, and proliferative retinopathy. Logistic regression models were performed to evaluate the relationships between retinopathy, stroke, and dementia, respectively. Independent relationships between retinopathy and all-cause mortality were assessed using Cox regression models, before and after adjusting for covariates. All analyses were adjusted for the complex survey design.

Results: Of 5,543 participants aged ≥18 years with gradable retinal imaging, 696 had retinopathy, 289 had stroke, and 597 had dementia. Mean age of subjects was 56.3 ± 11.7 years. Retinopathy was associated with higher risk of stroke (adj OR 2.39, P <0.001) and dementia (adj OR 1.68, P =0.005). Over a median duration of 118 months (IQR 111-125), there was a dose-dependent relationship between severity of retinopathy and all-cause mortality (adjusted hazard ratios were 1.0, 1.5, 2.4, 3.4 across retinopathy severity; P =0.021). The Figure shows the age-adjusted cumulative mortality curves by retinopathy severity.

Conclusions: Participants with retinopathy have a greater than 2-fold increase in stroke risk and a 1.7-fold increase in dementia risk. Having more severe retinopathy confers a higher risk of death after adjusting for age and vascular risk factors. The retina may serve as a tissue biomarker in intervention trials for cerebrovascular and neurodegenerative diseases.

Cilostazol Versus Aspirin for Secondary Stroke Prevention: Systematic Review and Meta-Analysis

OBJECTIVES

Cilostazol has promise as an alternative to aspirin for secondary stroke prevention given its vasodilatory and anti-inflammatory properties in addition to platelet aggregation inhibition. We aimed to conduct a systematic review and meta-analysis to estimate the efficacy and safety of cilostazol compared to aspirin for stroke prevention in patients with previous stroke or transient ischemic attack (TIA).

MATERIALS AND METHODS

We searched PubMed and the Cochrane Central Register of Controlled Trials from 1996 to 2019. Randomized clinical trials that compared cilostazol to aspirin and reported the endpoints of ischemic stroke, intracranial hemorrhage and any bleeding were included. A random-effects estimate was computed based on the Mantel-Haenszel method. The pooled risk estimates with 95% confidence intervals were compared between cilostazol and aspirin.

RESULTS

The search identified 5 randomized clinical trials comparing cilostazol vs. aspirin for secondary stroke prevention that collectively enrolled 7240 patients, all from Asian countries (3615 received cilostazol and 3625 received aspirin). Pooled results from the random-effects model showed that cilostazol was associated with significantly lower risk of recurrent ischemic stroke (RR 0.68; 95% CI, 0.54 to 0.87), intracranial hemorrhage (RR 0.42; 95% CI, 0.27 to 0.65) and any bleeding (RR 0.71; 95% CI, 0.55 to 0.91).

CONCLUSIONS

This meta-analysis suggests that cilostazol is more effective than aspirin in preventing recurrent ischemic stroke with lower risk of intracranial hemorrhage and other bleeding. Since all trials to date are from Asian countries, confirmatory trials of cilostazol for secondary stroke prevention in other populations are needed.

Absence of Consistent Sex Differences in Outcomes From Symptomatic Carotid Endarterectomy and Stenting Randomized Trials

BACKGROUND AND PURPOSE

CREST (Carotid Revascularization Endarterectomy Versus Stenting Trial) reported a higher periprocedural risk for any stroke, death, or myocardial infarction for women randomized to carotid artery stenting (CAS) compared with women randomized to carotid endarterectomy (CEA). No difference in risk by treatment was detected for women relative to men in the 4-year primary outcome. We aimed to conduct a pooled analysis among symptomatic patients in large randomized trials to provide more precise estimates of sex differences in the CAS-to-CEA risk for any stroke or death during the 120-day periprocedural period and ipsilateral stroke thereafter.

METHODS

Data from the Carotid Stenosis Trialists' Collaboration included outcomes from symptomatic patients in EVA-3S (Endarterectomy Versus Angioplasty in Patients With Symptomatic Severe Carotid Stenosis), SPACE (Stent-Protected Angioplasty Versus Carotid Endarterectomy in Symptomatic Patients), ICSS (International Carotid Stenting Study), and CREST. The primary outcome was any stroke or death within 120 days after randomization and ipsilateral stroke thereafter. Event rates and relative risks were estimated using Poisson regression; effect modification by sex was assessed with a sex-by-treatment-by-trial interaction term, with significant interaction defined a priori as P≤0.10.

RESULTS

Over a median 2.7 years of follow-up, 433 outcomes occurred in 3317 men and 1437 women. The CAS-to-CEA relative risk of the primary outcome was significantly lower for women compared with men in 1 trial, nominally lower in another, and nominally higher in the other two. The sex-by-treatment-by-trial interaction term was significant (P=0.065), indicating heterogeneity among trials. Contributors to this heterogeneity are primarily differences in periprocedural period. When the trials are nevertheless pooled, there were no significant sex differences in risk in any follow-up period.

CONCLUSIONS

There were significant differences between trials in the magnitude of sex differences in treatment effect (CAS-to-CEA relative risk), indicating pooling data from these trials to estimate sex differences might not be valid. Whether sex is acting as an effect modifier of the CAS-to-CEA treatment effect in symptomatic patients remains uncertain. Registration: URL: https://www.clinicaltrials.gov; Unique identifier: NCT00190398 (EVA-3S) and NCT00004732 (CREST). URL: https://www.isrctn.com; Unique identifier: ISRCTN57874028 (SPACE) and ISRCTN25337470 (ICSS).

Higher Risk for Reintervention in Patients after Stenting for Radiation-Induced Internal Carotid Artery Stenosis: A Single-Center Analysis and Systematic Review

BACKGROUND

This study aimed to review short- and long-term outcomes of all carotid artery stenting (CAS) in patients with radiation-induced (RI) internal carotid artery (ICA) stenosis compared with patients with atherosclerotic stenosis (AS).

METHODS

We performed a single-center, multisite case-control study of transfemoral carotid artery intervention in patients stented for RI or AS. Cases of stented RI carotid arteries were identified using a CAS database covering January 2000 to December 2019. These patients were randomly matched 2:1 with stented patients because of AS by age, sex, and year of CAS. A conditional logistic regression model was performed to estimate the odds of reintervention in the RI group. Finally, a systematic review was performed to assess the outcomes of RI stenosis treated with CAS.

RESULTS

There were 120 CAS in 113 patients because of RI ICA stenosis. Eighty-nine patients (78.8%) were male, and 68 patients (60.2%) were symptomatic. The reasons for radiation included most commonly treatment for diverse malignancies of the head and neck in 109 patients (96.5%). The mean radiation dose was 58.9 ± 15.6 Gy, and the time from radiation to CAS was 175.3 ± 140.4 months. Symptoms included 31 transient ischemic attacks (TIAs), 21 strokes (7 acute and 14 subacute), and 17 amaurosis fugax. The mean National Institutes of Health Stroke Scale in acute strokes was 8.7 ± 11.2. In asymptomatic patients, the indication for CAS was high-grade stenosis determined by duplex ultrasound. All CAS were successfully completed. Reinterventions were more frequent in the RI ICA stenosis cohort compared with the AS cohort (10.1% vs. 1.4%). Reinterventions occurred in 14 vessels, and causes for reintervention were restenosis in 12 followed by TIA/stroke in two vessels. On conditional regression modeling, patients with RI ICA stenosis were at a higher risk for reintervention (odds ratio = 7.1, 95% confidence interval = 2.1-32.8; P = 0.004). The mean follow-up was 33.7 ± 36.9 months, and the mortality across groups was no different (P = 0.12).

CONCLUSIONS

In our single-center, multisite cohort study, patients who underwent CAS for RI ICA stenosis experienced a higher rate of restenosis and a higher number of reinterventions compared with CAS for AS. Although CAS is safe and effective for this RI ICA stenosis cohort, further data are needed to reduce the risk of restenosis, and close patient surveillance is warranted. In our systematic review, CAS was considered an excellent alternative option for the treatment of patients with RI ICA stenosis. However, careful patient selection is warranted because of the increased risk of restenosis on long-term follow-up.

Mitigating the effects of COVID-19 pandemic on controlling vascular risk factors among participants in a carotid stenosis trial

Introduction

The COVID-19 pandemic has presented challenges to managing vascular risk factors with in-person follow-up of patients with asymptomatic carotid stenosis enrolled in the CREST2 trial. CREST2 is comparing intensive medical management alone versus intensive medical management plus revascularization with endarterectomy or stenting. We performed a study to evaluate the feasibility of a home-based program for testing blood pressure (BP) and low-density lipoprotein (LDL) in CREST2.

Methods

This study involved 45 patients at 10 sites in the CREST2 trial. The initial patients were identified by the Medical Management Core (MMC) as high-risk patients defined by stage 2 hypertension, LDL > 90 mg/dl, or both. If a patient at the site declined participation, another was substituted. All patients who agreed to participate were sent a BP monitoring device and a commercially available at-home lipid test kit that uses a self-performed finger-stick blood sample that was resulted to the patient. Training on the use of the equipment and obtaining the risk factor results was done by the study coordinator by telephone.

Results

Ten of the 130 currently active CREST2 sites participated, 8 in the LDL portion and 5 in the BP portion (3 sites did both). Twenty-six BP devices and 23 lipid tests were sent to patients. Of the 26 patients who obtained BP readings with the devices, 9 were out of the study target and adjustments in BP medications were made in 3. Of the 23 patients sent LDL tests, 13 were able to perform the test showing 7 were out of target, leading to adjustments in lipid medications in 4.

Conclusion

This study established the feasibility of at-home monitoring of BP and LDL in a clinical trial and identified implementation challenges prior to widespread use in the trial. (ClinicalTrials.gov number NCT02089217)

Rationale, Design, and Implementation of Intensive Risk Factor Treatment in the CREST2 Trial

BACKGROUND AND PURPOSE

The CREST2 trial (Carotid Revascularization and Medical Management for Asymptomatic Carotid Stenosis) is comparing intensive medical management (IMM) alone to IMM plus revascularization with carotid endarterectomy or transfemoral carotid artery stenting for preventing stroke or death within 44 days after randomization or ipsilateral ischemic stroke thereafter. There are extensive clinical trial data on outcomes after revascularization of asymptomatic carotid stenosis, but not for IMM. As such, the experimental treatment in CREST2 is IMM, which is described in this article.

METHODS

IMM consists of aspirin 325 mg/day and intensive risk factor management, primarily targeting systolic blood pressure <130 mm Hg (initially systolic blood pressure <140 mm Hg) and LDL (low-density lipoprotein) cholesterol <70 mg/dL. Secondary risk factor targets focus on tobacco smoking, non-HDL (high-density lipoprotein), HbA1c (hemoglobin A1c), physical activity, and weight. Risk factor management is performed by site personnel and a lifestyle coaching program delivered by telephone. We report interim risk factor data on 1618 patients at baseline and last follow-up through 24 months.

RESULTS

The mean baseline LDL of 80.5 mg/dL improved to 66.7 mg/dL. The mean baseline systolic blood pressure of 139.7 mm Hg improved to 130.3 mm Hg. The proportion of patients in-target improved from 43% to 61% for systolic blood pressure <130 mm Hg and from 45% to 67% for LDL<70 mg/dL (both changes P<0.001).

CONCLUSIONS

The rigorous multimodal approach to intensive stroke risk factor management in CREST2 has resulted in significant improvements in risk factor control that will enable a comparison of cutting-edge medical care to revascularization in patients with asymptomatic carotid stenosis. Registration: URL: https://www.clinicaltrials.gov. Unique identifier: NCT02089217.

Prevalence of Intracranial Aneurysms in Patients with Infrarenal Abdominal Aortic Aneurysms: A Multicenter Experience

Prior studies suggest high prevalence of intracranial aneurysms (IA) in patients with infrarenal abdominal aortic aneurysms (AAA). We reviewed our multicenter experience in clinical detection/treatment of IAs in AAA patients and estimated the risk of IA in patients with AAA relative to patients without AAA. We reviewed cases of vascular surgery infrarenal AAA repairs at three Mayo Clinic sites from January 1998 to December 2018. Concurrent controls were randomly matched in a 1:1 ratio by age, sex, smoking history, and head imaging characteristics. Conditional logistic regression was used to calculate odds ratios. We reviewed 2,300 infrarenal AAA repairs. Mean size of AAA at repair was 56.9 ± 11.4 mm; mean age at repair, 75.8 ± 8.0 years. 87.5% of the cases ( n  = 2014) were men. Head imaging was available in 421 patients. Thirty-seven patients were found to have 45 IAs for a prevalence of 8.8%. Mean size of IA was 4.6 ± 3.5 mm; mean age at IA detection, 72.0 ± 10.8 years. Thirty (81%) out of 37 patients were men. Six patients underwent treatment for IA: four for ruptured IAs and two for unruptured IAs. All were diagnosed before AAA repair. Treatment included five clippings and one coil-assisted stenting. Time from IA diagnosis to AAA repair was 16.4 ± 11.0 years. Two of these patients presented with ruptured AAA, one with successful repair and a second one that resulted in death. Odds of IA were higher for patients with AAA versus those without AAA (8.8% [37/421] vs. 3.1% [13/421]; OR 3.18; 95% confidence interval, 1.62-6.27, p  < 0.001). Co-prevalence of IA among patients with AAA was 8.8% and is more than three times the rate seen in patients without AAA. All IAs were diagnosed prior to AAA repair. Surveillance for AAA after IA treatment could have prevented two AAA ruptures and one death.

Quality Assurance for Carotid Stenting in the CREST-2 Registry

BACKGROUND

The CREST-2 Registry (C2R) was approved by National Institute of Neurological Disorders and Stroke-National Institutes of Health in September 2014 with Centers for Medicare & Medicaid Services, U.S. Food and Drug Administration, and industry collaboration to enroll patients undergoing CAS. The registry credentials interventionists and promotes optimal patient selection, procedural-technique, and outcomes.

OBJECTIVES

This study reports periprocedural outcomes in a cohort of carotid artery stenting (CAS) performed for asymptomatic and symptomatic carotid stenosis.

METHODS

Asymptomatic patients with ≥70% and symptomatic patients with ≥50% carotid stenosis, ≤80 years of age, and at standard or high risk for carotid endarterectomy are eligible for enrollment. Interventionists are credentialed by a multispecialty committee that reviews experience, lesion selection, technique, and outcomes. The primary endpoint was a composite of stroke and death (S/D) in the 30-day periprocedural period. Myocardial infarction and access-site complications were assessed as secondary outcomes.

RESULTS

As of December 2018, 187 interventionists from 98 sites in the United States performed 2,219 CAS procedures in 2,141 patients with primary atherosclerosis (78 were bilateral). The mean age of the cohort was 68 years, 65% were male, and 92% were white; 1,180 (55%) were for asymptomatic disease, and 961 (45%) were for symptomatic disease. All U.S. Food and Drug Administration-approved stents and embolic protection devices were represented. The 30-day rate of S/D was 1.4% for asymptomatic, 2.8% for symptomatic, and 2.0% for all patients.

CONCLUSIONS

C2R is the first national registry for CAS cosponsored by federal and industry partners. CAS was performed by experienced operators using appropriate patient selection and optimal technique. In that setting, a broad group of interventionists achieved very low periprocedural S/D rates for asymptomatic and symptomatic patients.

The CREST-2 experience with the evolving challenges of COVID-19: A clinical trial in a pandemic

The coronavirus disease 2019 pandemic has disrupted the lives of whole communities and nations. The multinational multicenter National Institute of Neurological Disorders and Stroke Carotid Revascularization and Medical Management for Asymptomatic Carotid Stenosis Trial stroke prevention trial rapidly experienced the effects of the pandemic and had to temporarily suspend new enrollments and shift patient follow-up activities from in-person clinic visits to telephone contacts. There is an ethical obligation to the patients to protect their health while taking every feasible step to ensure that the goals of the trial are successfully met. Here, we describe the effects of the pandemic on the trial and steps that are being taken to mitigate the effects of the pandemic so that trial objectives can be met.

Collateral Recruitment Is Impaired by Cerebral Small Vessel Disease

Background and Purpose- Cerebral small vessel disease (SVD) is associated with increased stroke risk and poor stroke outcomes. We aimed to evaluate whether chronic SVD burden is associated with poor recruitment of collaterals in large-vessel occlusive stroke. Methods- Consecutive patients with middle cerebral artery or internal carotid artery occlusion presenting within 6 hours after stroke symptom onset who underwent thrombectomy from 2012 to 2017 were included. The prespecified primary outcome was poor collateral flow, which was assessed on baseline computed tomographic angiography (poor, ≤50% filling; good, >50% filling). Markers of chronic SVD on brain magnetic resonance imaging were rated for the extent of white matter hyperintensities, enlarged perivascular spaces, chronic lacunar infarctions and cerebral microbleeds using the Standards for Reporting Vascular Changes on Neuroimaging criteria. Severity of SVD was quantified by adding the presence of each SVD feature, with a total possible score of 0 to 4; each SVD type was also evaluated separately. Multivariable logistic regression analyses were performed to evaluate the relationships between SVD and poor collaterals, with adjustment for potential confounders. Results- Of the 100 eligible patients, the mean age was 65±16 years, median National Institutes of Health Stroke Scale score was 15, and 68% had any SVD. Poor collaterals were observed in 46%, and those with SVD were more likely to have poor collaterals than patients without SVD (aOR, 1.9 [95% CI, 1.1-3.2]). Of the SVD types, poor collaterals were significantly associated with white matter hyperintensities (aOR, 2.9 per Fazekas increment [95% CI, 1.6-5.3]) but not with enlarged perivascular spaces (adjusted odds ratio [aOR], 1.3 [95% CI, 0.4-4.0]), lacunae (aOR, 2.1 [95% CI, 0.6-7.1]), or cerebral microbleeds (aOR, 2.1 [95% CI, 0.6-7.8]). Having a greater number of different SVD markers was associated with a higher odds of poor collaterals (crude trend P<0.001; adjusted P=0.056). There was a dose-dependent relationship between white matter hyperintensity burden and poor collaterals: adjusted odds of poor collaterals were 1.5, 3.0, and 9.7 across Fazekas scores of 1 to 3 (Ptrend=0.015). No patient with an SVD score of 4 had good collaterals. Conclusions- Chronic cerebral SVD is associated with poor recruitment of collaterals in large vessel occlusive stroke. A prospective study to elucidate the potential mechanism of how SVD may impair the recruitment of collaterals is ongoing.

Timing of procedural stroke and death in asymptomatic patients undergoing carotid endarterectomy: individual patient analysis from four RCTs

BACKGROUND

The effectiveness of carotid endarterectomy (CEA) for stroke prevention depends on low procedural risks. The aim of this study was to assess the frequency and timing of procedural complications after CEA, which may clarify underlying mechanisms and help inform safe discharge policies.

METHODS

Individual-patient data were obtained from four large carotid intervention trials (VACS, ACAS, ACST-1 and GALA; 1983-2007). Patients undergoing CEA for asymptomatic carotid artery stenosis directly after randomization were used for the present analysis. Timing of procedural death and stroke was divided into intraoperative day 0, postoperative day 0, days 1-3 and days 4-30.

RESULTS

Some 3694 patients were included in the analysis. A total of 103 patients (2·8 per cent) had serious procedural complications (18 fatal strokes, 68 non-fatal strokes, 11 fatal myocardial infarctions and 6 deaths from other causes) [Correction added on 20 April, after first online publication: the percentage value has been corrected to 2·8]. Of the 86 strokes, 67 (78 per cent) were ipsilateral, 17 (20 per cent) were contralateral and two (2 per cent) were vertebrobasilar. Forty-five strokes (52 per cent) were ischaemic, nine (10 per cent) haemorrhagic, and stroke subtype was not determined in 32 patients (37 per cent). Half of the strokes happened on the day of CEA. Of all serious complications recorded, 44 (42·7 per cent) occurred on day 0 (20 intraoperative, 17 postoperative, 7 with unclear timing), 23 (22·3 per cent) on days 1-3 and 36 (35·0 per cent) on days 4-30.

CONCLUSION

At least half of the procedural strokes in this study were ischaemic and ipsilateral to the treated artery. Half of all procedural complications occurred on the day of surgery, but one-third after day 3 when many patients had been discharged.

Abstract TP123: Baseline Differences in Risk Factor Control Between CREST-2 and SAMMPRIS

Baseline Differences in Risk Factor Control and Medication Use Between 2 Trials Employing Intensive Medical Management (SAMMPRIS & CREST2)

Background: The CREST2 trial Intensive Medical Management (IMM) protocol was adapted from the SAMMPRIS trial. However, since the 2011 publication of initial results of SAMMPRIS, there has been a greater appreciation for the importance of risk factor control in patients at risk of stroke associated with atherosclerosis. Therefore, we sought to determine differences in baseline risk factor control and medication use between SAMMPRIS and CREST2.

Methods: Baseline risk factor and medication use data from 451 patients enrolled in SAMMPRIS (2008-2011) with severe symptomatic intracranial atherosclerosis and 1473 patients enrolled in CREST2 (2014-2019) with severe asymptomatic carotid stenosis were compared using the Chi-square test and t-test.

Results: The Table shows baseline risk factor values and medications. SAMMPRIS patients were younger but had significantly worse risk factor control than CREST2 patients for all measures. There was no significant difference in statin use at baseline, but the mean SAMMPRIS subjects’ LDL was 16.1 mg/dL higher than in CREST2. CREST2 patients had higher rates of use of angiotensin receptor blockers (ARB), calcium channel blockers (CCB), and thiazides, but lower rates of use of angiotensin converting enzyme (ACE) inhibitors.

Conclusions: Despite being older, CREST2 patients have significantly better baseline risk factor profiles than SAMMPRIS patients. This could be due to greater appreciation of the importance of risk factor control and healthy lifestyle habits for stroke prevention or more aggressive treatment targets in guideline recommendations. Although risk factor control appears to be improving since SAMMPRIS, many CREST2 patients are still not meeting recommended risk factor goals at baseline and may benefit from IMM protocols.

Abstract WP403: Trends and Predictors of Intracranial Hemorrhage in Patients With Advanced Heart Failure on Left Ventricular Assist Device From 2005 to 2014 in the U.S

Introduction: Left ventricular assist device (LVAD) is known to extend survival in patients with advanced heart failure but it is associated with intracranial cranial hemorrhage (ICH). In the last decade, the use of LVAD substantially increased along with advances in LVAD technology, but there is limited data regarding the trends of ICH risk and predictors in patients with LVAD.

Methods: We included the patients aged≥18 years with primary diagnosis of LVAD hospitalized in the US from 2005 to 2014 using the National Inpatient Sample. We computed the survey weighted percentages with ICH across the 10-year study period and assessed whether the proportions changed over time. Predictors of ICH were evaluated using the multivariable logistic regression model. All analyses were appropriately adjusted for the survey design variables to account for the complex survey design.

Results: Of 33,246 hospitalizations, 568 (1.7%) had ICH. The number of LVAD placement has increased from 873 in year 2005 to 5,175 in year 2014. However, the risk of ICH remained largely unchanged from 1.7% to 2.3% (linear trend: p=0.604). The adjusted odds of ICH was increased with the presence one of the following variables: female sex (odds ratio [OR]: 1.58, 95% confidence interval [CI] 1.03-2.43), history of ischemic stroke (OR: 3.13, 95% CI 1.86-5.28), and Charlson Comorbidity Index (CCI) of ≥3 (OR: 77.40, 95% CI 10.03-597.60).

Conclusions: Despite advances in LVAD technology and its increased use in patients with advanced heart failure, the risk of ICH has remained relatively unchanged. High CCI and history of ischemic stroke were associated with higher odds of ICH in patients with LVAD. With the advent of magnetically levitated centrifugal-flow LVAD, future trend of ICH may change and further research efforts are needed to prevent ICH in patients with LVAD.

Enhancing the Informed Consent Process Using Shared Decision Making and Consent Refusal Data from the CLEAR III Trial

BACKGROUND

The process of informed consent in National Institutes of Health randomized, placebo-controlled trials is poorly studied. There are several issues regarding informed consent in emergency neurologic trials, including a shared decision-making process with the patient or a legally authorized representative about overall risks, benefits, and alternative treatments.

METHODS

To evaluate the informed consent process, we collected best and worst informed consent practice information from a National Institutes of Health trial and used this in medical simulation videos to educate investigators at multiple sites to improve the consent process. Clot Lysis: Evaluating Accelerated Resolution of Intraventricular Hemorrhage Phase III (CLEAR III) (clinicaltrials.gov, NCT00784134) studied the effect of intraventricular alteplase (n = 251) versus saline (placebo) injections (n = 249) for intraventricular hemorrhage reduction. Reasons for ineligibility (including refusing to consent) for all screen failures were analyzed. The broadcasted presentation outlined best practices for doctor-patient interactions during the consenting process, as well as anecdotal, study-specific reasons for consent refusal. Best and worst consent elements were then incorporated into a simulation video to enhance the informed consent process. This video was disseminated to trial sites as a webinar around the midpoint of the trial to improve the consent process. Pre- and post-intervention consent refusals were compared.

RESULTS

During the trial, 10,538 patients were screened for eligibility, of which only three were excluded due to trial timing. Pre-intervention, 77 of 5686 (1.40%) screen eligible patients or their proxies refused consent. Post-intervention, 55 of 4849 (1.10%) refused consent, which was not significantly different from pre-intervention (P = 0.312). The incidence of screen failures was significantly lower post-intervention (P = 0.006), possibly due to several factors for patient exclusion.

CONCLUSION

The informed consent process for prospective randomized trials may be enhanced by studying and refining best practices based on trial-specific plans and patient concerns particular to a study.

Abstract TP131: Carotid Stenosis and Polyvascular Disease

Background: Presence of atherosclerotic disease in more than one vascular bed (polyvascular disease) is associated with an increased risk of long-term vascular events. In the setting of asymptomatic carotid stenosis, the predictors of disease in other vascular beds is not well delineated.

Objective: To identify the frequency and predictors of disease in other vascular beds the CREST 2 randomized trial population with hemodynamically significant stenosis.

Methods: Recorded baseline characteristics among CREST 2 participants included: demographics, past medical history, lifestyle factors, and laboratory studies. Each variable was tested against three potential definitions of disease in other beds (cardiac, peripheral arterial disease (PAD) or disease in cardiac + PAD). Statistical analysis was done with Chi square and t tests as appropriate.

Results: Data from 1447 patients were available for analysis. In these subjects with carotid disease, 51% also had cardiac disease, 24% also had PAD, and 16% had disease in in both cardiac and PAD. There was no relationship between age or race and presence of disease in other beds. Those with cardiac disease were more likely to be male. Diabetes, hypertension, hypercholesterolemia, and former history of smoking were all more common in those with either cardiac and PAD (TABLE). Elevated triglyceride and low HDL levels were also associated with all three definitions of disease in other beds. Those with either PAD or cardiac + PAD were more likely to be current smokers.

Conclusions: Among CREST 2 participants, several medical conditions and lifestyle factors were associated with an increased frequency of disease in other vascular beds. Smoking, in particular, appears to be more common in those with PAD. Future analyses will address whether those with disease in other beds have higher rates of stroke or death.

Abstract TP199: Association Between Left Atrial Enlargement and Poor Collaterals in Large Vessel Occlusion

Introduction: Left atrial enlargement (LAE) is associated with atrial fibrillation, a frequent cause of large vessel occlusion (LVO) leading to ischemic stroke. Leptomeningeal collaterals protect tissue from ischemia, but the association between collaterals and structural heart disease is not well described. We aim to investigate the association between LAE and cerebral collaterals during acute LVO when microvasculature, vasodilation, and chronotropic competence are critically important.

Hypothesis: Left atrial enlargement is associated with poor collaterals.

Methods: We reviewed consecutive patients presenting with middle cerebral and internal carotid LVO who underwent thrombectomy from 2012 to 2017. Patients with CT angiogram of the head and echocardiogram were included. Poor collaterals were defined as ≤ 50% filling on CT angiogram. LAE was defined as left atrial volume index ≥ 35 mL/m 2 . Multivariate logistic regression analysis was performed to evaluate the relationship between LAE and poor collaterals with adjustment for age and hypertension.

Results: There were 128 eligible patients. The mean age was 68± 15 years, median NIHSS was 17, and 51 (39.8%) had LAE. Baseline characteristics are described in the table. Poor collaterals were observed in 50 (39%) patients. Patients with LAE were more likely to have poor collaterals compared to those with normal left atrial size (52.9% vs. 29.9%, p=0.009). After adjusting for age and hypertension, a trend towards association remained (OR 2.00, p=0.089).

Conclusion: Our results indicate that patients with LVO and LAE were more likely to have poor collaterals. Further research is warranted to determine the cause of the association. One possibility is shared pathophysiology affecting both cardiac and cerebral vasculature such as microvascular disease or endothelial dysfunction. Alternatively, structural heart disease causing chronotropic incompetence may lead to poor collateral filling.

Abstract WP172: Advancing Age is a Predictor of Poor Collaterals

Introduction: Robust leptomeningeal collaterals protect the brain from ischemia, yet the determinants of poor collaterals have not been established. We aimed to identify predictors of poor collaterals in patients with large vessel occlusive stroke.

Methods: Consecutive patients with large vessel occlusive stroke who underwent thrombectomy at 2 academic medical centers (derivation cohort/validation cohort) from 2012-2017 were included. Poor collaterals were defined as ≤50% filling on CT angiogram. Pre-specified predictors of poor collaterals were analyzed with adjusted logistic regression models: demographics (age, sex, race), risk factors (hypertension, diabetes, atrial fibrillation, smoking), hemodynamics (blood pressure, cardiac output, troponin), metabolic (hyperglycemia, hyponatremia, uremia), hematologic (anemia, leukocytosis, thrombocytosis) and neuroimaging evidence of chronic cerebral small-vessel disease and chronic steno-occlusive arterial disease.

Results: Of the 248 total patients, poor collaterals were detected in 107 (43%). Mean age was 71±14y vs. 63±16y in patients with poor vs good collaterals, respectively (p<.001). There were 136 patients in the derivation cohort; 54 (48%) patients with poor collaterals. Multivariable modeling identified that older age (OR 1.8, p<.001), hyperglycemia (OR 2.4, p=.029) and white matter hyperintensities (WMH) (OR 6.1, p=.003) were independent predictors of poor collaterals in the derivation cohort. The validation cohort consisted of 136 patients; 53 (39%) had poor collaterals, of which older age (OR 1.4, p=.015), thrombocytosis (OR 24.0, p=.012), and WMH (OR 6.7, p=.018) were significant predictors of poor collaterals. Age and WMH were the only significant predictors of poor collaterals across the derivation and validation cohorts. When pooled the cohorts, older age (OR=1.5, p<.001), thrombocytosis (OR=7.6, p=.001) and WMH (OR=6.4, p<.001) were significant predictors of poor collaterals.

Conclusions: We have identified that advanced age, WMH, and thrombocytosis are predictors of poor collaterals. Future studies to explore the effect of vascular aging on collateral therapeutics are indicated.

Abstract TP141: Can the Human Eye Match a Computer Algorithm in Identifying Hypoperfusion in Asymptomatic Carotid Artery Stenosis?

Background: Perfusion weighted imaging on MRI (MRP) and computerized tomography perfusion (CTP) are increasingly required to manage large vessel disease. Computerized algorithms can quantify perfusion data, but the programs are expensive and not widely used outside acute stroke evaluation. We aimed to determine how well human observers can identify asymmetries in cerebral perfusion images compared with an automated computer algorithm.

Methods: Ten clinicians experienced in treating carotid artery disease (4 vascular neurologists, 3 neuroradiologists, 1 vascular surgeon, 1 neurosurgeon, 1 interventional radiologist) were given 28 post-processed, color-coded, axial-slice MRP scans from patients in the Carotid Revascularization Endovascular versus Stenting Trial - Hemodynamics (CREST-H) study. All patients had >70%, unilateral, asymptomatic carotid artery stenosis and had varying degrees of time-to-peak (TTP) delay on the side of stenosis, ranging from 0 to 2 secs, quantified by a semi-automated system that computes quantitative perfusion maps, using deconvolution of tissue and arterial signals (Olea, Cambridge, MA). A minimum volume of 10cc was required for a given TTP delay. Clinicians were asked to determine asymmetry (y/n) and side of occlusion for each case. Number of correct responses that matched the computer output were tallied.

Results: We averaged correct responses by the 10 clinicians for cases at each increment of TTP delay; (Figure). At TTP delays ≥1.5 seconds, accuracy was ≥80%. At 1.25 sec accuracy fell to 60%, and at ≤ 1 sec, accuracy was ≤50%. For TTP=0 (no asymmetry), accuracy was 71%.

Conclusions: Visual impression of hemodynamic asymmetry among experienced clinicians was reasonably accurate for TTP delays ≥1.5 seconds, but declined with more subtle asymmetries. Depending on the clinical impact of TTP delays (for CREST-H: correlation with cognitive decline), experienced clinicians may perform as well as an automated algorithm.

Associations of Perioperative Variables With the 30-Day Risk of Stroke or Death in Carotid Endarterectomy for Symptomatic Carotid Stenosis

Background and Purpose- This analysis was performed to assess the association between perioperative and clinical variables and the 30-day risk of stroke or death after carotid endarterectomy for symptomatic carotid stenosis. Methods- Individual patient-level data from the 5 largest randomized controlled carotid trials were pooled in the Carotid Stenosis Trialists' Collaboration database. A total of 4181 patients who received carotid endarterectomy for symptomatic stenosis per protocol were included. Determinants of outcome included carotid endarterectomy technique, type of anesthesia, intraoperative neurophysiological monitoring, shunting, antiplatelet medication, and clinical variables. Stroke or death within 30 days after carotid endarterectomy was the primary outcome. Adjusted risk ratios (aRRs) were estimated in multilevel multivariable analyses using a Poisson regression model. Results- Mean age was 69.5±9.2 years (70.7% men). The 30-day stroke or death rate was 4.3%. In the multivariable regression analysis, local anesthesia was associated with a lower primary outcome rate (versus general anesthesia; aRR, 0.70 [95% CI, 0.50-0.99]). Shunting (aRR, 1.43 [95% CI, 1.05-1.95]), a contralateral high-grade carotid stenosis or occlusion (aRR, 1.58 [95% CI, 1.02-2.47]), and a more severe neurological deficit (mRS, 3-5 versus 0-2: aRR, 2.51 [95% CI, 1.30-4.83]) were associated with higher primary outcome rates. None of the other characteristics were significantly associated with the perioperative stroke or death risk. Conclusions- The current results indicate lower perioperative stroke or death rates in patients operated upon under local anesthesia, whereas a more severe neurological deficit and a contralateral high-grade carotid stenosis or occlusion were identified as potential risk factors. Despite a possible selection bias and patients not having been randomized, these findings might be useful to guide surgeons and anesthetists when treating patients with symptomatic carotid disease.

Treatment of migraine in patients with CADASIL: A systematic review and meta-analysis

Background

Migraine is a common and often refractory feature for individuals with cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) without consensus guidelines for treatment. Migraine treatment poses a theoretical risk within this unique population with precarious cerebrovascular autoregulation, given the vasomodulatory influence of many antimigraine medications. In this systematic review and meta-analysis, we evaluate the frequency and efficacy of treatments for migraine in individuals with CADASIL.

Methods

A search protocol was designed to include all available publications reporting antimigraine therapies for CADASIL. Individual responses to medications were categorized as unfavorable, neutral, or favorable. Responses across medication classes were compared using the Mann-Whitney U test.

Results

Thirteen studies were included, yielding a cohort of 123 individuals with a median age of 53 years (range: 23-83 years), with 61% (75/123) being women. No controlled trials were identified. Simple analgesics (35.8%, 44/123) and beta-blockers (22.0%, 27/123) were the most common abortive and prophylactic strategies, respectively. Over half (54.4%) of all patients had used more than 1 medication sequentially or concomitantly. Beta-blockers were significantly associated with a neutral or unfavorable response (13.5%, 22/163, p = 0.004). We found no significant associations among other medication categories.

Conclusions

Migraine in CADASIL remains a formidable therapeutic challenge, with patients often tried on several medications. Antimigraine prophylaxis with beta-blockers may be contraindicated relative to other common therapies in CADASIL. Controlled studies are needed to rigorously evaluate the safety and efficacy of antimigraine therapies in this population.

Safety of Carotid Revascularization in Patients With a History of Coronary Heart Disease

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Background and Purpose—

We investigated whether procedural stroke or death risk of carotid artery stenting (CAS) compared with carotid endarterectomy (CEA) is different in patients with and without history of coronary heart disease (CHD) and whether the treatment-specific impact of age differs.

Methods—

We combined individual patient data of 4754 patients with symptomatic carotid stenosis from 4 randomized trials (EVA-3S [Endarterectomy Versus Angioplasty in Patients With Symptomatic Severe Carotid Stenosis], SPACE [Stent-Protected Angioplasty Versus Carotid Endarterectomy], ICSS [International Carotid Stenting Study], and CREST [Carotid Revascularization Endarterectomy Versus Stenting Trial]). Procedural risk was defined as any stroke or death ≤30 days after treatment. We compared procedural risk between both treatments with Cox regression analysis, stratified by history of CHD and age (<70, 70–74, ≥75 years). History of CHD included myocardial infarction, angina, or coronary revascularization.

Results—

One thousand two hundred ninety-three (28%) patients had history of CHD. Procedural stroke or death risk was higher in patients with history of CHD. Procedural risk in patients treated with CAS compared with CEA was consistent in patients with history of CHD (8.3% versus 4.6%; hazard ratio [HR], 1.96; 95% CI, 0.67–5.73) and in those without (6.9% versus 3.6%; HR, 1.93; 95% CI, 1.40–2.65; P_interaction=0.89). In patients with history of CHD, procedural risk was significantly higher after CAS compared with CEA in patients aged ≥75 (CAS-to-CEA HR, 2.78; 95% CI, 1.32–5.85), but not in patients aged <70 (HR, 1.71; 95% CI, 0.79–3.71) and 70 to 74 years (HR, 1.09; 95% CI, 0.45–2.65). In contrast, in patients without history of CHD, procedural risk after CAS was higher in patients aged 70 to 74 (HR, 3.62; 95% CI, 1.80–7.29) and ≥75 years (HR, 2.64; 95% CI, 1.52–4.59), but equal in patients aged <70 years (HR, 1.05; 95% CI, 0.63–1.73; 3-way P_interaction=0.09).

Conclusions—

History of CHD does not modify procedural stroke or death risk of CAS compared with CEA. CAS might be as safe as CEA in patients with history of CHD aged <75 years, whereas for patients without history of CHD, risk after CAS compared with CEA was only equal in those aged <70 years.

Immediate and Delayed Procedural Stroke or Death in Stenting Versus Endarterectomy for Symptomatic Carotid Stenosis

Background and Purpose- Stenting for symptomatic carotid stenosis (carotid artery stenting [CAS]) carries a higher risk of procedural stroke or death than carotid endarterectomy (CEA). It is unclear whether this extra risk is present both on the day of procedure and within 1 to 30 days thereafter and whether clinical risk factors differ between these periods. Methods- We analyzed the risk of stroke or death occurring on the day of procedure (immediate procedural events) and within 1 to 30 days thereafter (delayed procedural events) in 4597 individual patients with symptomatic carotid stenosis who underwent CAS (n=2326) or CEA (n=2271) in 4 randomized trials. Results- Compared with CEA, patients treated with CAS were at greater risk for immediate procedural events (110 versus 42; 4.7% versus 1.9%; odds ratio, 2.6; 95% CI, 1.9-3.8) but not for delayed procedural events (59 versus 46; 2.5% versus 2.0%; odds ratio, 1.3; 95% CI, 0.9-1.9; interaction P=0.006). In patients treated with CAS, age increased the risk for both immediate and delayed events while qualifying event severity only increased the risk of delayed events. In patients treated with CEA, we found no risk factors for immediate events while a higher level of disability at baseline and known history of hypertension were associated with delayed procedural events. Conclusions- The increased procedural stroke or death risk associated with CAS compared with CEA was caused by an excess of events occurring on the day of procedure. This finding demonstrates the need to enhance the procedural safety of CAS by technical improvements of the procedure and increased operator skill. Higher age increased the risk for both immediate and delayed procedural events in CAS, mechanisms of which remain to be elucidated. Clinical Trial Registration- URL: https://clinicaltrials.gov . Unique identifier: NCT00190398. URL: http://www.isrctn.com . Unique identifier: ISRCTN57874028. URL: http://www.isrctn.com . Unique identifier: ISRCTN25337470. URL: https://clinicaltrials.gov . Unique identifier: NCT00004732.

Prediction Models for Clinical Outcome After a Carotid Revascularization Procedure

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Background and Purpose—

Prediction models may help physicians to stratify patients with high and low risk for periprocedural complications or long-term stroke risk after carotid artery stenting or carotid endarterectomy. We aimed to evaluate external performance of previously published prediction models for short- and long-term outcome after carotid revascularization in patients with symptomatic carotid artery stenosis.

Methods—

From a literature review, we selected all prediction models that used only readily available patient characteristics known before procedure initiation. Follow-up data from 2184 carotid artery stenting and 2261 carotid endarterectomy patients from 4 randomized trials (EVA-3S [Endarterectomy Versus Angioplasty in Patients With Symptomatic Severe Carotid Stenosis], SPACE [Stent-Protected Angioplasty Versus Carotid Endarterectomy], ICSS [International Carotid Stenting Study], and CREST [Carotid Revascularization Endarterectomy Versus Stenting Trial]) were used to validate 23 short-term outcome models to estimate stroke or death risk ≤30 days after the procedure and the original outcome measure for which the model was developed. Additionally, we validated 7 long-term outcome models for the original outcome measure. Predictive performance of the models was assessed with C statistics and calibration plots.

Results—

Stroke or death ≤30 days after the procedure occurred in 158 (7.2%) patients after carotid artery stenting and in 84 (3.7%) patients after carotid endarterectomy. Most models for short-term outcome after carotid artery stenting (n=4) or carotid endarterectomy (n=19) had poor discriminative performance (C statistics ranging from 0.49–0.64) and poor calibration with small absolute risk differences between the lowest and highest risk groups and overestimation of risk in the highest risk groups. Long-term outcome models (n=7) had a slightly better performance with C statistics ranging from 0.59 to 0.67 and reasonable calibration.

Conclusions—

Current models did not reliably predict outcome after carotid revascularization in a trial population of patients with symptomatic carotid stenosis. In particular, prediction of short-term outcome seemed to be difficult. Further external validation of existing prediction models or development of new prediction models is needed before such models can be used to support treatment decisions in individual patients.

Secular Trends in Procedural Stroke or Death Risks of Stenting Versus Endarterectomy for Symptomatic Carotid Stenosis

BACKGROUND

Over the past decades, stroke risk associated with carotid disease has decreased, reflecting improvements in medical therapy and a more rigorous control of vascular risk factors. It is less clear whether the procedural risk of carotid revascularization has declined over time.

METHODS

We analyzed temporal changes in procedural risks among 4597 patients with symptomatic carotid stenosis treated with carotid artery stenting (n=2326) or carotid endarterectomy (n=2271) in 4 randomized trials between 2000 and 2008, using generalized linear mixed-effects models with a random intercept for each source trial. Models were additionally adjusted for age and other baseline characteristics predicting treatment risk. The primary outcome event was any procedural stroke or death, occurring during or within 30 days after revascularization.

RESULTS

The procedural stroke or death risk decreased significantly over time in all patients (unadjusted odds ratio per year, 0.91; 95% CI, 0.85-0.97; P=0.006). This effect was driven by a decrease in the carotid endarterectomy group (unadjusted odds ratio per year, 0.82; 95% CI, 0.73-0.92; P=0.003), whereas no significant decrease was found after carotid artery stenting (unadjusted odds ratio, 0.96; 95% CI, 0.88-1.04; P=0.33). Carotid endarterectomy patients had a lower procedural stroke or death risk compared with carotid artery stenting patients, and the difference significantly increased over time (interaction P=0.031). After adjustment for baseline characteristics, the results remained essentially the same.

CONCLUSIONS

The risk of stroke or death associated with carotid endarterectomy for symptomatic carotid stenosis decreased over an 8-year period, independent of clinical predictors of procedural risk. No corresponding reduction in procedural risk was seen in patients treated with stenting.

CLINICAL TRIAL REGISTRATION

URL: https://www.clinicaltrials.gov; http://www.isrctn.com. Unique identifier: NCT00190398 (EVA-3S), NCT00004732 (CREST), ISRCTN57874028 (SPACE), and ISRCTN25337470 (ICSS).

Factors influencing credentialing of interventionists in the CREST-2 trial

BACKGROUND

The Carotid Revascularization and Medical Management for Asymptomatic Carotid Stenosis Trial (CREST-2) is a pair of randomized trials assessing the relative efficacy of carotid revascularization in the setting of intensive medical management (IMM) in patients with asymptomatic high-grade atherosclerotic stenosis. One of the trials assesses IMM with or without carotid artery stenting (CAS). Given the low risk of stroke in nonrevascularized patients receiving IMM, it is essential that there be low periprocedural risk of stroke for CAS if it is to show incremental benefit. Thus, credentialing of interventionists to ensure excellence is vital. This analysis describes the protocol-driven approach to credentialing of CAS interventionists for CREST-2 and its outcomes.

METHODS

To be eligible to perform stenting in CREST-2, interventionists needed to be credentialed on the basis of a detailed Interventional Management Committee (IMC) review of data from their last 25 consecutive cases during the past 24 months along with self-reported lifetime experience case numbers. When necessary, additional prospective cases performed in a companion registry were requested after webinar training. Here we review the IMC experience from the first formal meeting on March 21, 2014 through October 14, 2017.

RESULTS

The IMC had 102 meetings, and 8311 cases submitted by 334 interventionists were evaluated. Most were either cardiologists or vascular surgeons, although no single specialty made up the majority of applicants. The median total experience was 130 cases (interquartile range [IQR], 75-266; range, 25-2500). Only 9% (30/334) of interventionists were approved at initial review; approval increased to 46% (153/334) after submission of new cases with added training and re-review. The median self-reported lifetime case experience for those approved was 211.5 (IQR, 100-350), and the median number of cases submitted for review was 30 (IQR, 27-35). The number of CAS procedures performed per month (case rate) was the only factor associated with approval during the initial cycle of review (P < .00001).

CONCLUSIONS

Identification of interventionists who were deemed sufficiently skilled for CREST-2 has required substantial oversight and a controlled system to judge current skill level that controls for specialty-based practice variability, procedural experience, and periprocedural outcomes. High-volume interventionists, particularly those with more recent experience, were more likely to be approved to participate in CREST-2. Primary approval was not affected by operator specialty.

Severity of White Matter Hyperintensities and Effects on All-Cause Mortality in the Mayo Clinic Florida Familial Cerebrovascular Diseases Registry

OBJECTIVE

To compare all-cause mortality rates across the severity range of white matter hyperintensities (WMH).

PATIENTS AND METHODS

Between October 26, 2010, and October 5, 2017, the ongoing Mayo Clinic Florida Familial Cerebrovascular Diseases Registry prospectively enrolled 1011 diverse participants with and without cerebrovascular disease. T2-weighted magnetic resonance imaging of the brain was used to evaluate WMH in 455 participants using the Fazekas scale. Fazekas deep WMH (FD) and periventricular WMH (FPV) scores (0-3 points) were assigned on the basis of WMH severity. Kaplan-Meier survival analyses, Cox proportional hazards models, and estimated hazard ratios compared survival rates across FD and FPV categories. The Fisher exact and χ² tests evaluated the relationship of categorical variables, and the Kruskal-Wallis test measured the relationship of continuous variables across FD and FPV categories. All tests were performed at a P<.05 significance level.

RESULTS

Over a median follow-up of 3.06 years (range, 0.00-6.96 years), 96 deaths occurred. Higher FD scores corresponded to a higher likelihood of mortality (P<.001). Participants with an FD score of 3 were 4.69 (95% CI, 2.60-8.46) times more likely to die compared with those with an FD score of 0. Participants with higher FPV scores had a higher likelihood of mortality (P<.001). Participants with an FPV score of 3 were 7.04 (95% CI, 3.39-14.62) times more likely to die compared with those with an FPV score of 0. Once adjusted, age and baseline functional status explained most of the survival differences among the FD scores.

CONCLUSION

Associations between all-cause mortality rates across the severity range of WMH were observed in the Registry. Further studies are warranted to understand the clinical importance of WMH in other clinical populations.

Long-term outcomes of stenting and endarterectomy for symptomatic carotid stenosis: a preplanned pooled analysis of individual patient data

BACKGROUND

The risk of periprocedural stroke or death is higher after carotid artery stenting (CAS) than carotid endarterectomy (CEA) for the treatment of symptomatic carotid stenosis. However, long-term outcomes have not been sufficiently assessed. We sought to combine individual patient-level data from the four major randomised controlled trials of CAS versus CEA for the treatment of symptomatic carotid stenosis to assess long-term outcomes.

METHODS

We did a pooled analysis of individual patient-level data, acquired from the four largest randomised controlled trials assessing the relative efficacy of CAS and CEA for treatment of symptomatic carotid stenosis (Endarterectomy versus Angioplasty in Patients with Symptomatic Severe Carotid Stenosis trial, Stent-Protected Percutaneous Angioplasty of the Carotid Artery versus Endarterectomy trial, International Carotid Stenting Study, and Carotid Revascularization Endarterectomy versus Stenting Trial). The risk of ipsilateral stroke was assessed between 121 days and 1, 3, 5, 7, 9, and 10 years after randomisation. The primary outcome was the composite risk of stroke or death within 120 days after randomisation (periprocedural risk) or subsequent ipsilateral stroke up to 10 years after randomisation (postprocedural risk). Analyses were intention-to-treat, with the risk of events calculated using Kaplan-Meier methods and Cox proportional hazards analysis with adjustment for trial.

FINDINGS

In the four trials included, 4775 patients were randomly assigned, of whom a total of 4754 (99·6%) patients were followed up for a maximum of 12·4 years. 21 (0·4%) patients immediately withdrew consent after randomisation and were excluded. Median length of follow-up across the studies ranged from 2·0 to 6·9 years. 129 periprocedural and 55 postprocedural outcome events occurred in patients allocated CEA, and 206 and 57 for those allocated CAS. After the periprocedural period, the annual rates of ipsilateral stroke per person-year were similar for the two treatments: 0·60% (95% CI 0·46-0·79) for CEA and 0·64% (0·49-0·83) for CAS. Nonetheless, the periprocedural and postprocedural risks combined favoured CEA, with treatment differences at 1, 3, 5, 7, and 9 years all ranging between 2·8% (1·1-4·4) and 4·1% (2·0-6·3).

INTERPRETATION

Outcomes in the postprocedural period after CAS and CEA were similar, suggesting robust clinical durability for both treatments. Although long-term outcomes (periprocedural and postprocedural risks combined) continue to favour CEA, the similarity of the postprocedural rates suggest that improvements in the periprocedural safety of CAS could provide similar outcomes of the two procedures in the future.

FUNDING

None.

Abstract WMP41: Predictors of Poor Collaterals in Large-Vessel Occlusive Stroke

Introduction: Robust leptomeningeal collaterals protect brain from ischemia, yet the determinants of poor collaterals remains unclear. We aimed to identify predictors of poor collaterals in patients with large-vessel occlusive stroke.

Methods: We analyzed 112 consecutive patients with middle cerebral artery ± internal carotid artery occlusion from 2012-2016 who presented within 6 hours after stroke symptoms onset. Collaterals on baseline CT-angiogram (poor collaterals ≤50% filling, good collaterals >50% filling) were reviewed blinded to clinical data. Pre-specified predictors of poor collaterals were analyzed with adjusted logistic regression models: including known predictors (age, vascular risk factors and metabolic derangements) and hypothesized predictors (low cardiac output, elevated inflammatory markers, and imaging evidence for chronic cerebral small-vessel disease and chronic steno-occlusive arterial disease).

Results: The mean age was 67± 16 years, there were 48% women, 57% white, and median NIHSS was 15 (IQR 11-20). Poor collaterals at baseline were detected in 48%. Multivariable modeling identified that age (aOR 1.8 per 10 years; 95% CI 1.3-2.6; p<0.001), black race (aOR 2.1; 95% CI 1.0-4.5; p=0.043), high blood glucose level (aOR 2.4 per 100 mg/dl; 95% CI 1.1-5.1; p=0.029), and high WMH burden (aOR 6.1; 95%CI 1.8-20.4; p=0.003) were independent predictors of poor collaterals. Associations between low cardiac output, elevated inflammatory markers, intracranial atherosclerosis and poor collaterals did not reach statistical significance (Table).

Conclusions: We have identified that advanced age, black race, hyperglycemia, and white matter hyperintensities are predictors of poor collaterals. Independent replication study at another institution is ongoing to further explore the hypothesized predictors.

Abstract TP527: Baseline Physical Activity Profiles in CREST-2 Trial Participants

Background: The importance of physical activity in preventing major vascular events has received increased attention in the past decade. Due to the inclusion of the INTERVENT lifestyle modification program, the CREST2 trial provides a unique opportunity to study physical activity profiles in patients with severe asymptomatic extracranial carotid stenosis.

Hypothesis: Based on data from a trial of intracranial stenosis patients, we aimed to evaluate the hypothesis that <40% of carotid stenosis subjects will have optimal physical activity levels. We also assessed key subgroups to determine patterns of physical activity.

Methods: We analyzed 1087 CREST2 participants with baseline data on physical activity. The Physician-based Assessment and Counseling for Exercise (PACE) score is recorded for each patient and dichotomized as “in target” (4-8 points) or “out of target” (<4 points). A PACE score of <4 indicates a subject who does not engage in regular exercise. Results are analyzed for the entire trial. Chi square testing and t-tests were performed for evaluation of subgroup differences.

Results: The mean age of the study population is 69.5±7.8 years (60% male). The median PACE score at baseline is 4.0 (mean 3.8±2.1; IQR 2 to 6). The Table shows baseline characteristics of patients by mean PACE score. Being male, not having diabetes mellitus, having a body mass index <30kg/m2, being a non-smoker, and not having a history of peripheral arterial disease were associated with significantly higher mean PACE scores (P<0.01).

Conclusions: We have defined several patient groups with asymptomatic carotid stenosis that have suboptimal physical activity. These results provide opportunities for targeted efforts to improve primary stroke prevention. These baseline data will also allow investigators to determine if trial involvement and the INTERVENT program leads to improvement in the level of physical activity.